Condition based maintenance for complex engineering assets: A multi-layered modelling approach

Condition based maintenance for complex assets is still problematic, especially, when the asset has severe fault propagation among their components. In this paper, a layered model is proposed to represent a complex asset as a collection of interdependent components. The upper layer uses a Continuous Time Markov chain to calculate the optimal inspection interval and maintenance threshold considering accelerated deterioration caused by fault propagation. The lower layer models the fault propagation in components and in turn calculates the accelerated deterioration rate. By decomposing the model in this manner, we can overcome the problem of exponentially increased complexity with the number of components in the asset. We present numerical analysis on the upper layer model as well as closed-form solution for a simple case. We also show that the new approach results in improved inspection and maintenance schedules. © 2012 IFAC